the ntsb still can't say for sure why two of the batteries overheated and one caught fire on that plane in boston. but they know boeing's safety system failed. experts say it looks like this investigation will last for a while. >> suddenly 787 will be on the ground for an indefinite period. whether that's two months, four months, six months or more, i have no way of knowing. but it's not going to be back in the air any time soon. >> united airlines is the only u.s. carrier to have any dreamliners. they have six. the ceo says he has confidence the problem will be fixed and customers will come back. shep. >> shepard: dan springer in seattle, chunks of concrete go flying as a sewer explosion tears up a downtown street and it tops our news around the world in 80 seconds. china. security cameras captured the moment the road suddenly burst open in a southern province. one angle appears to show three adults and a child standing a few feet away. officials say nobody was hurt. the blast destroyed some 250 feet of roadway. authorities are investigating the cause. >>> australia. torrential rains t